UNIVERSITY  OF  CALIFORNIA  PUBLICATIONS 

COLLEGE  OF  AGRICULTURE 

AGRICULTURAL  EXPERIMENT  STATION 

BERKELEY,  CALIFORNIA 


THE   POMEGRANATE 


BY 


ROBERT  W.  HODGSON 


BULLETIN  No.  276 

January,  1917 


UNIVERSITY  OF  CALIFORNIA  PRESS 

BERKELEY 

1917 


Benjamin  Ii>k  Wheeler,  President  of  the  University. 

EXPERIMENT  STATION  STAFF 

HEADS    OF    DIVISIONS 

Thomas  Foesyth  Hunt,  Director. 
Edward  J.  Wickson,  Horticulture    (Emeritus). 

Herbert  J.  Webber,  Director  Citrus  Experiment  Station;    Plant  Breeding. 
Hubert  E.  Van  Norman,  Vice-Director;  Dairy  Management. 
William   A.   Setchell,  Botany. 
Myer  E.  Jaffa,  Nutrition. 

Robert  H.  Loughridge,  Soil  Chemistry  and    Physics    (Emeritus). 
Charles  W.  Woodworth,  Entomology. 
Ralph  E.  Smith,  Plant  Pathology. 
J.  Eliot  Coit,  Citriculture. 
John  W.  Gilmore,  Agronomy. 
Charles  F.  Shaw,  Soil  Technology. 

John  W.  Gregg,  Landscape  Gardening  and  Floriculture. 
Frederick  T.  Bioletti,  Viticulture  and  Enology. 
Warren  T.  Clarke,  Agricultural  Extension. 
John  S.  Burd,  Agricultural  Chemistry. 
Charles  B.  Lipman,  Soil  Chemistry  and  Bacteriology. 
Clarence  M.  Haring,  Veterinary  Science  and  Bacteriology. 
Ernest  B.  Babcock,  Genetics. 
Gordon  H.  True,  Animal  Husbandry. 
James  T.  Barrett,  Plant  Pathology. 
Fritz  W.  Woll,  Animal  Nutrition. 
A.  V.  Stubenrauch,  Pomology. 
Walter  Mulford,  Forestry. 
W.  P.  Kelley,  Agricultural  Chemistry. 
H.  J.  Quayle,  Entomology. 
Elwood  Mead,  Rural  Institutions. 
J.  B.  Davidson,  Agricultural  Engineering. 
H.  S.  Reed,  Plant  Physiology. 
D.  T.  Mason,  Forestry. 

William  G.  Hummel,  Agricultural  Education. 
John  E.  Dougherty,  Poultry  Husbandry. 
S.  S.  Rogers,  Olericulture. 
*Frank  Adams,  Irrigation  Investigations. 
H.  S.  Baird,  Dairy  Industry. 
David  N.  Morgan,  Assistant  to  the  Director. 
Mrs.  D.  L.  Bunnell,  Librarian. 

Division  of  Citriculture 
J.  Eliot  Coit  Ira  J.  Condit 


*  In  co-operation  with  office   of  Public  Roads   and  Rural   Engineering,   U.   S. 
Department  of  Agriculture. 


THE  POMEGRANATE 

By  ROBERT  W.  HODGSON 


FOREWORD 

This  bulletin  was  first  submitted  as  a  thesis  for  the  Bachelor's  de- 
gree in  the  College  of  Agriculture.  The  thesis  was  prepared  under 
the  supervision  of  the  undersigned,  who  considered  part  of  the  mono- 
graph of  sufficient  general  interest  to  warrant  publication.  The 
thesis  has  therefore  been  rearranged  and  edited,  the  larger  part  of 
the  historical  study  being  omitted.  On  the  other  hand  the  subjects  of 
more  vital  interest  to  growers,  such  as  pruning  and  orchard  manage- 
ment have  been  somewhat  expanded  after  additional  observations  and 
investigations  were  made  in  the  orchards  during  the  past  summer. 

We  wish  to  acknowledge  the  kindly  assistance  of  many  growers 
who  have  so  cheerfully  given  specimens  and  information  and  lent  their 
aid  in  various  ways. 

J.  Eliot  Coit. 

INTRODUCTION 

According  to  the  census  reports  for  1910  pomegranates  were  grown 
in  quantities  large  enough  to  receive  special  attention  from  the  census 
officials  in  the  following  states  :  California,  Arizona,  Georgia,  Alabama, 
Nevada,  and  Utah.  In  the  remaining  southern  states  they  are  grown 
to  some  extent  but  not  commercially.  The  total  production  in  1910 
is  given  at  145,840  pounds,  valued  at  $3,909. 

At  the  present  time,  California  has  about  125  to  150  acres  planted 
in  pomegranates  as  follows :  Porterville  district,  60  to  65  acres ;  Fresno 
district,  25  to  30  acres;  Imperial  Valley,  15  to  25  acres;  and  the  rest 
of  the  state,  25  to  30  acres.  In  1915  one  firm  in  the  Porterville  district 
handled  7219  boxes,  which  netted  the  growers  $6,136.15,  or  twice  as 
much  as  was  received  for  the  crop  of  the  whole  United  States  in  1910. 
Evidently  the  industry  is  growing. 

The  pomegranate  thrives  in  all  the  interior  valleys  of  California 
and  in  Arizona,  producing  heavy  crops  of  excellent  fruit.  There  is 
no  good  reason  why  this  fruit  may  not  be  produced  cheaply  and  in 
any  quantity  the  market  demand  may  justify.  The  only  hindrance 
to  a  rapid  extension  of  pomegranate  planting  in  California  is  the  lack 
of  market  demand.     This  is  easily  accounted  for  by  the  ignorance  on 


164  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

the  part  of  the  American  public  of  the  good  qualities  of  the  fruit. 
Spanish-speaking  peoples  fully  appreciate  the  pomegranate  and  con- 
sume the  fruit  in  considerable  quantities,  while  the  consumers  in  the 
neighborhood  of  the  large  fruit  markets  of  the  United  States,  being 
accustomed  to  the  apple,  peach,  grape,  and  orange,  hesitate  before  a 
strange  fruit,  to  the  good  points  of  which  they  have  not  been  educated. 
The  extension  of  the  pomegranate  industry  is  therefore  largely  de- 
pendent on  the  education  of  the  public.  The  people  of  the  United 
States  are  notably  large  consumers  of  fruit  and  the  present  wide- 
spread interest  in  new  fruits  indicates  a  demand  for  greater 
diversification.  That  pomegranates  are  included  in  this  new  demand 
is  shown  by  the  increased  sales  and  fair  prices  mentioned  above.     The 


Wt?W^*?W  '  ;* 


' 


Fig.  1. — Commercial  pomegranate  orchard  near  Porterville. 

introduction  of  a  new  fruit  into  the  markets  is  necessarily  a  slow 
process,  but  the  pomegranate  is  such  a  worthy  fruit  that  it  will  be 
sure  to  win  a  greatly  increased  consumption,  especially  if  assisted  by 
a  little  judicious  advertising. 

HISTORY 

The  pomegranate  has  been  grown  from  most  ancient  times.  All 
the  botanical,  historical,  and  philological  data  so  far  examined  agree 
in  showing  that  our  modern  species,  Punica  granatum,  is  a  native  of 
Persia  and  adjacent  countries  where  it  was  highly  esteemed  before  the 
advent  of  the  almond,  apricot,  or  peach. 

Like  the  fig,  vine,  and  olive,  it  claims  a  place  in  the  earliest  annals 
of  history  and  was  classed  in  point  of  utility  with  the  grain-bearing 
plants  and  honey,  these  constituting  an  important  part  of  the  food  of 
the  nations  of  antiquity  in  their  early  stages  of  civilization. 


THE  POMEGRANATE  165 

Inasmuch  as  the  pomegranate  was  mentioned  many  times  in  early 
Grecian  history  before  the  founding  of  Rome,  it  is  evident  that  the 
Greeks  were  familiar  with  this  fruit  a  considerable  time  before  it  was 
introduced  into  Rome  by  way  of  Carthage.  Homer  mentions  the 
pomegranate  twice  in  the  Odyssey  as  a  fruit  common  to  the  gardens 
of  Phoenicia  and  Phrygia.  Herodotus,  the  Greek  historian,  states  that 
when  the  Persians  under  Xerxes  invaded  Greece  there  was  a  regiment 
or  battalion  known  as  the  "Pomegranate  Brigade.' '  These  soldiers 
constituted  Xerxes'  own  bodyguard,  and  carried  spears  with  golden 
pomegranates  at  the  lower  end  instead  of  spikes.  The  battle  of 
M|arathon  occurred  about  490  B.C.,  hence  we  can  see  how  early  the 
pomegranate  was  recorded  in  Grecian  history.  Theophrastus  described 
it  carefully  in  his  Natural  History  written  about  350  years  before  the 
Christian  area.  Pomegranates  are  mentioned  several  times  in  the  Old 
Testament,  but  only  as  cultivated  plants.  The  Israelites  had  become 
familiar  with  the  tree  and  fruit  in  Egypt,  for  in  the  long  wandering 
through  the  Wilderness  they  murmured  for  "the  fruits  of  Egypt,  the 
fig,  the  vine,  and  the  pomegranate."  Pomegranates  were  evidently 
held  in  high  esteem,  for  King  Solomon  sings  of  "an  orchard  of  pome- 
granates with  pleasant  fruits. " 

Frequent  mention  is  made  of  the  pomegranate  by  Roman  writers. 
Pliny  considered  it  a  most  valuable  fruit  and  declared  that  the  best 
kinds  came  from  Carthage.  Galen  and  Dioscorides,  Roman  physicians, 
mention  its  medicinal  qualities.  Palladius  and  Columella  call  attention 
to  the  fruit  several  times  in  their  writings.  In  Spain  it  flourished  and 
came  to  be  regarded  as  the  symbol  of  the  Golden  Age  in  Granada. 
To-day  the  wide-spread  thickets  of  pomegranates  in  Spain  furnish 
almost  the  only  signs  of  the  Moorish  occupation.  Ibu-al-Awam,  a 
Moor- Spaniard  of  the  twelfth  century,  described  eleven  varieties  of 
pomegranates  growing  at  that  time.  Granada,  in  Spain,  owes  its 
name  to  the  far-spread  fame  of  its  pomegranates,  the  fruit  reaching  a 
high  degree  of  perfection  in  its  gentle  climate. 

During  the  middle  ages  the  fruit  came  to  be  known  as  Pomum 
granatum,  or  seeded  apple.  By  contraction  this  has  resulted  in  our 
present  common  name  pomegranate.  Linnaeus  gave  it  the  scientific 
name  Punica  granatum. 

After  Cortez  conquered  Mexico  in  1521,  the  Jesuit  padres  soon 
began  their  missionary  work  among  the  Indians.  With  them  they 
brought  the  fruits  of  France  and  Spain,  and  among  these  the  pome- 
granate. 

All  the  fruits  from  the  older  missions  in  Mexico  were  carried  north- 
ward and  planted  in  the  new  mission  gardens  in  California.    In  these 


166  UNIVERSITY  OF   CALIFORNIA EXPERIMENT  STATION 

gardens  may  still  be  seen  some  of  the  old  olive  and  date  trees  and 
pomegranate  bushes.  In  1792  Vancouver  found  an  orchard  at  Mission 
San  Buena  Ventura  in  which  pomegranates  were  growing  together 
with  apples,  pears,  plums,  figs,  oranges,  grapes  and  peaches.  Robinson 
mentions  an  orchard  of  pomegranates  at  the  Mission  San  Gabriel. 

The  type  of  pomegranate  grown  at  these  missions  is  of  a  mongrel 
seedling  origin,  but  is  of  fair  quality  and  well  liked  by  many  people. 
It  has  a  rather  wide  distribution.  Since  1850  many  new  varieties 
have  been  introduced,  some  by  way  of  the  southern  states,  principally 
Florida  and  Georgia,  but  mainly  from  the  Mediterranean  countries 
and  China.  Until  recently  most  of  the  plantings  in  California  have 
been  seedlings  or  cuttings  taken  indiscriminately.  The  number  of 
different  forms  now  growing  in  the  state  is  therefore  large  and  varied 
and  furnishes  excellent  material  for  the  selection  of  better  commercial 
varieties.  Several  superior  varieties  have  appeared  and  are  now  being 
propagated.  The  most  promising  of  these  is  the  Wonderful,  which  is 
the  only  pomegranate  now  being  grown  commercially  in  California. 

Although  the  exact  date  of  the  introduction  of  the  pomegranate 
into  the  eastern  United  States  is  not  known,  it  is  probable  that  it  was 
taken,  along  with  the  orange  and  other  fruits,  to  Florida  at  an  early 
date.  However,  it  was  not  until  the  middle  of  the  nineteenth  century 
that  attention  was  directed  to  the  culture  of  this  fruit  in  the  south. 
At  that  time  varieties  from  California  and  southern  Europe  were  intro- 
duced and  a  few  plantings  made,  chiefly  as  garden  and  door-yard  trees. 
However,  pomegranate  growing  has  never  become  a  commercial  in- 
dustry although  the  shrub  is  now  quite  common  throughout  the 
southern  states.  Some  very  good  varieties  are  found,  but  little  attempt 
has  been  made  at  developing  a  market  for  the  fruit,  and  it  is  prin- 
cipally grown  for  home  use.  Pomegranate  plants  will  grow  as  far  north 
as  Washington,  D.  C,  but  they  will  seldom  mature  fruit  farther  north 
than  eastern  North  Carolina,  and  at  that  latitude  fruiting  is  quite 
uncertain. 

BOTANY 

There  is  much  disagreement  among  systematic  botanists  as  to  the 
proper  classification  of  the  pomegranate,  but  all  agree  that  it  is  a 
member  of  the  Order  Myrtifloreae  or  Myrtales.  The  number  of  groups 
or  families  in  this  order  varies  from  nine  to  twenty,  according  to  the 
systematist  classifying  them.  Some  place  the  pomegranate  in  the  Myr- 
tle group  and  some  place  it  directly  in  the  Pomegranate  family,  but 
all  agree  that  the  family  is  distinct  and  contains  only  one  genus.     The 


THE  POMEGRANATE 


167 


following  paragraphs  contain  a  description   of  the  more   importanl 
botanical  characters  of  this  genus. 

Punica  granatum,  L.     The  Pomegranate. 

A  large  shrub  or  small  tree;  bushy  in  growth;  usually  deciduous,  though 
there  are  varieties  which  are  practically  evergreen.  Leaves  without  glands 
and  marginal  veins;  mostly  opposite;  lanceolate,  long,  or  obovate;  obtuse;  en- 
tire; glabrous;  young  growth  red-veined;  bright  glossy  green;  average  one-half 
inch  wide  by  three  inches  long. 

Branches  slender;  twiggy;  nearly  cylindrical;  somewhat  thorny;  new  growth 
four-angled.  A  peculiarity  of  the  thorns  is  that  they  are  modified  stem  struc- 
tures and  not  of  leaf  origin.  The  small  twigs  often  terminate  in  these  thorns, 
as  do  usually  also  the  short  side  shoots.     These  vary  somewhat  in  length  but 


Fig.  2. — Cross  section  of  pomegranate  flower  showing  position  of  carpels. 


average  one-fourth  to  three-fourths  of  an  inch.     Varieties  vary  a  great  deal 
in  thorniness. 

Flowers  axillary;  solitary,  or  in  small  clusters;  borne  mainly  at  the  tips 
of  the  branches  in  a  zone  on  the  outer  edge  of  the  tree.  Produced  on  short 
spurs  grown  on  two  or  three-year-old  wood;  average  inch  to  inch  and  a  half 
in  length.  Calyx  stiff;  tubular;  showy;  orange  or  red  in  color;  five  to  seven 
lobes  or  sepals;  crowned  with  crumpled  petals;  bright  scarlet  or  white  in  color; 
lanceolate  to  obovate  in  shape;  equal  in  number  to  the  sepals  and  inserted 
between  them.  Stamens  numerous;  inserted  on  inner  wall  of  calyx-tube. 
Ovary  inferior;  spherical;  imbedded  in  fleshy  calyx-tube  or  receptacle;  sur- 
mounted by  single  long,  slender  style.  Stigma  small;  discoid.  Ovary  contains 
seven  to  fifteen  carpels  or  locules,  arranged  in  two  whorls  or  series,  one  in- 
terior and  lower,  containing  three  carpels;  the  other  exterior  and  upper,  con- 
taining six  to  twelve  carpels.  Ovary  ripens  into  a  large,  baccate,  many-celled, 
many-seeded,  pome-like  berry,  crowned  with  a  showy,  persistent  calyx.  The 
rind  or  pericarp,  formed  by  the  wall  of  the  calyx-tube,  is  tough  and  hard. 


168  UNIVERSITY  OF   CALIFORNIA EXPERIMENT  STATION 

The  morphological  development  of  the  fruit  is  peculiar  (Fig.  2). 
During  the  growth  the  carpels  of  the  upper  series  are  turned  around 
as  though  they  had  been  rotated  180  degrees  in  a  plane  parallel  to 
the  long  diameter  of  the  fruit.  In  the  mature  fruit,  therefore,  we 
find  the  carpels  of  the  lower  tier  occupying  their  original  positions,  at- 
tached to  the  base  of  the  fruit.  In  the  upper  series,  however,  though 
irregular  in  size  and  shape,  they  are  attached  to  the  periphery  of 
the  fruit. 

Each  locule  contains  a  variable  number  of  small,  angular,  berry- 
like fruit-bodies,  the  angularity  being  due  to  their  lying  closely  packed 
together  (Fig.  13).  Each  of  these  is  covered  with  a  thin  membrane 
which  encloses  a  fruity  mass  very  rich  in  juice.  The  fruity  mass  or 
aril  comprises  the  edible  portion  of  the  fruit.     It  arises  by  the  ex- 


Fig.  3. — Large  flower  with  perfect  ovary  compared  with  abortive  flower  showing 

merely  the  rudiment  of  an  ovary. 

ternal  portion  of  the  seed-coat  becoming  succulent.  The  arils  are 
transparent,  with  a  beautiful  clear  color  ranging  from  pale  pink  to 
dark  crimson,  and  contain  a  seed  of  variable  size,  enclosed  in  a  shell 
or  seed-coat  of  varying  degrees  of  hardness.  Within  the  seed-coat  the 
cotyledons  are  rolled  together  in  a  spiral  fashion. 

The  pomegranate  rind  is  tough  and  leathery  and  varies  in  color  from 
pale  yellow  to  deep  purple  red.  The  rind  itself  is  always  fairly  thin 
and  must  be  distinguished  from  the  pulp  or  rag.  In  some  varieties  the 
amount  of  rag  is  large  and  the  rind  is  lined  with  a  layer  which  gives 
it  the  appearance  of  being  thick.  In  others  this  is  not  the  case,  and 
the  arils  extend  to  the  rind  itself.  Thus  it  is  possible  for  a  pome- 
granate to  have  a  thin  rind  but  a  large  percent  of  rag  or  pulp,  and 
vice  versa.  The  pulp,  rind,  and  thin  separating  parchments  or  mem- 
branes are  all  bitter  and  astringent,  containing  appreciable  quantities 
of  tannin.    The  fruits  vary  from  three  to  six  inches  in  diameter. 


THE  POMEGRANATE 


169 


A  varying  percentage  of  pomegranate  flowers  is  sterile  and  does  not 
set  fruit,  falling;  early.  These  flowers,  which  are  not  as  long  as  the 
perfect  flowers,  have  the  pistil  reduced  in  varying  degrees,  in  some 
only  a  rudiment  being  present.  All  stages  in  its  development  may 
be  found  from  almost  none  to  the  large  pistil  with  long  style  in  the 
perfect  flower.     Ornamental  types  are  almost  entirely  sterile. 

Pomegranate  trees  and  bushes  are  very  graceful  in  form  and 
foliage,  having  a  marked  drooping,  willowy  effect  when  trained  to 


Fig.  4. — Showy  calyx-tube  and  petals  of  the  pomegranate  flower 


tree  or  arbor  form,  and  a  round,  compact,  bushy  shape  in  their  natural 
condition.  They  are  well  adapted  for  use  in  hedges,  having  a  strong 
tendency  to  a  knotty,  irregular  growth^  and  suckering  freely  from 
the  roots  and  crown.  This  suckering  habit  is  so  pronounced  that  in 
training  to  tree  form,  suckers  must  be  removed  very  frequently.  By 
careful  pruning  the  pomegranate  may  be  trained  into  a  small  tree 
reaching  a  height  of  fifteen  to  twenty  feet. 

The  pomegranate  is  valued  as  an  ornamental  tree  on  account  of  its 
bright  glossy  green  leaves  and  the  profusion  of  its  large  blossoms. 
These  are  produced  over  a  long  period  of  time,  from  April  to  Septem- 
ber, and  on  the  outer  portion  of  the  tree  so  that  the  flaming  red  of 


170 


UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 


both  the  petals  and  calyx-tube  forms  a  rich  contrast  to  the  dark  green 
foliage.  The  fruit  begins  to  ripen  in  September  and  if  not  picked 
hangs  on  the  tree  until  January.  Thus  for  nine  months  of  the  year, 
April  to  January,  the  tree  is  ornamental.  Pomegranates  are  rather 
slow  to  leaf  out  in  the  spring,  putting  out  leaves  at  about  the  same 
time  as  the  fig. 

The  plant  is  very  long-lived  as  compared  to  many  of  our  fruit 
trees.  Plants  are  still  living  in  the  mission  gardens,  which  were  planted 
by  the  early  padres.  At  Paris  and  Versailles  in  France  are  specimens 
which  are  known  to  have  fruited  for  over  two  centuries. 


Fig.  5. — Type  of  good  commercial  pomegranate. 

Some  of  the  botanical  relatives  of  the  pomegranate  are  the  delicious 
guava,  the  feijoa,  the  rose  apple,  cloves,  the  fuchsia,  and  loosestrife. 


HORTICULTURAL  VARIETIES 

There  are  two  general  types  of  pomegranates  growing  in  California 
at  the  present  time. 

White-flowered  Type. — This  sort  of  pomegranate  has  been  intro- 
duced within  the  last  twenty  or  thirty  years.  Some  varieties  belonging 
to  this  type  are  deciduous,  some  are  more  or  less  evergreen.  The  fruit 
is  round-oblate  or  obovate  in  form,  of  a  pale  lemon  or  fawn  color,  and 
the  rind  is  invariably  thick  and  soft.  The  edible  portion  is  small  to 
medium  in  amount ;  the  arils  are  large  and  translucent ;  and  the  seeds 
are  large  to  very  large,  with  thick  bony  seed-coats  rendering  them 
difficult  to  chew  and  inedible.     The  flavor  is  flat,  insipid,  and  lacking 


THE  POMEGRANATE 


171 


in  the  acid  element.  The  appearance  is  very  poor  and  the  fruit  has 
poor  keeping  quality.  It  is  very  easily  bruised  and  these  injuries 
become  conspicuous  in  storage  as  ugly  brown  blotches  which  detract 
from  the  appearance.  This  type  is  undesirable  and  is  not  being  propa- 
gated to  any  extent. 


Fig. 


6. — Type  of  fruit  worthless  for  commercial  purposes. 


Pink  or  Bed-flowered  Type. — This  type  includes  most  of  our  com- 
mon pomegranates  and  all  of  the  desirable  and  commercial  varieties. 
So  far  as  we  know,  the  tree  is  always  deciduous.  The  fruit  is  round 
oblate  or  obovate  in  form,  according  to  variety;  the  rind  varies  from 
thick  to  very  thin ;  the  edible  portion  is  small  to  large  in  amount ;  the 
arils  vary  much  in  size,  and  are  pale  pink  to  bright  crimson  in  color ; 
and  the  seeds  also  vary  in  size  and  range  in  hardness  from  the  so-called 


172  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

"seedless''  varieties,  in  which  the  seeds  are  edible,  to  very  hard  and 
bony  seeds.  The  fruits  vary  in  color  from  a  pale  lemon  yellow  washed 
with  light  pink  to  a  bright  crimson  with  a  deep  purple  tinge. 

Requirements  of  a  Good  Commercial  Pomegranate. — Fruit  medium 
to  large  in  size;  pink  or  bright  red  with  a  glossy  surface;  relatively 
free  from  splitting  at  maturity ;  length  of  calyx-tube  medium  or  short, 
with  the  lobes  reflexed  or  inflexed,  not  upright.  Rind  thin,  tough,  and 
well  adapted  to  shipping.  Flesh  abundant,  bright  red  or  crimson.  A 
small  amount  of  rag  or  pulp.  Seeds  small  in  proportion  to  the  aril ; 
tender  and  easily  eaten;  juice  abundant  and  well-colored;  flavor  rich, 
sprightly,  vinous  and  subacid. 

The  complete  list  of  varieties  is  long,  but  only  five  are  found  on 
the  market.  Of  these,  the  Wonderful  is  by  far  the  best.  This  variety 
occupies  the  same  relation  among  pomegranates  that  the  Washington 
Navel  does  among  winter  oranges  in  California.  On  account  of  its 
vigorous  growth  and  habit  of  regularly  bearing  large  crops  of  high 
quality  fruit,  it  is  a  universal  favorite.  At  the  present  time  fully 
75  per  cent  of  the  pomegranates  shipped  to  the  markets,  and  nearly 
all  of  the  newer  plantings,  are  of  the  Wonderful  variety. 

Wonderful. — About  1896  a  Mr.  Bearss  of  Porterville  obtained  a 
quantity  of  pomegranate  cuttings  from  Florida.  One  of  these  bore 
fruit  unlike  the  others,  and  proved  especially  good.  He  propagated 
this  and  called  it  the  Wonderful. 

Fruit  large  and  attractive ;  deep  purple-red,  glossy ;  flesh  deep 
crimson;  juice  abundant  and  deep  crimson;  flavor  excellent,  vinous, 
rich  and  sprightly;  seeds  fairly  tender;  rind  medium  in  thickness; 
calyx  medium  in  length.  A  very  good  shipper  and  commands  a 
premium  on  the  market.     (See  Fig.  12.) 

Paper  Shell. — Large,  attractive;  pale  yellow  washed  with  pink, 
glossy;  flesh  bright  red;  juice  abundant  and  bright  red;  flavor  good; 
seeds  fairly  tender;  rind  very  thin;  calyx  small.  Received  its  name 
on  account  of  its  thin  rind.  An  excellent  fruit  for  home  use.  Tree 
not  so  vigorous  as  Wonderful  or  Spanish  Ruby.  This  variety  was 
introduced  from  the  southern  states  and  is  probably  the  second  in 
importance  in  California. 

Spanish  Ruby. — Large,  attractive;  bright  red,  glossy;  flesh  crim- 
son; juice  abundant,  bright  red;  flavor  sweet  and  aromatic;  seeds 
fairly  tender;  rind  medium  in  thickness;  calyx  medium.  This  is 
another  variety  imported  from  the  South,  where  it  is  often  called  the 
Purple  Seeded  or  Purple  variety.  It  stands  third  in  importance  in 
California. 


THE  POMEGRANATE 


173 


Sweet  Fruited. — Medium  in  size;  pale  yellow,  lightly  striped  with 
pink;  flesh  pale  pink;  juice  moderate  in  amount;  flavor  pleasant  and 
aromatic;  seeds  fairly  tender;  rind  medium;  calyx  medium. 

Subacid. — Medium  in  size ;  pale  yellow  with  pink  flush ;  flesh  clear 
red;  juice  moderate  in  amount;  flavor  quite  tart  and  sour;  seeds  not 
edible,  but  readily  chewed ;  rind  thin,  calyx  large.  Very  much  like 
the  Sweet,  but  more  acid. 

Other  varieties  frequently  found  are  the  Badinar,  Dessia,  and  Sin 
Pepitas.  This  last  is  a  so-called  "seedless"  variety,  but  in  the  United 
States  at  least,  has  been  found  to  have  seeds,  although  they  are  quite 
tender  and  easilv  eaten. 


Fig.  7. — The  small  fruit  has  a  thick  rind  but  little  rag,  small  arils  and  large 
seeds.  The  large  fruit  has  thin  rind  and  much  rag,  large  arils  and  small  seeds. 
Neither  is  satisfactory. 

Varieties  occasionally  found  are  the  Jative,  Hermosillo,  Acid,  and 
others. 

The  Division  of  Seed  and  Plant  Introduction  of  the  U.  S.  Depart- 
ment of  Agriculture  has  made  135  to  140  introductions  of  pomegranates 
from  many  foreign  countries.  These  come  from  many  localities 
throughout  southern  Europe,  northern  Africa,  Asia  except  Siberia 
and  Japan,  and  Argentina.  A  number  of  these  plants  are  now  fruiting 
in  U.  S.  Government  gardens  at  Chico,  Butte  County,  and  at  Indio, 
Riverside  County.    Among  them  are  several  of  considerable  promise. 

Ornamental  varieties  grown  are  the  Double- flowered  and  Dwarf 
pomegranates.  These  may  have  red,  yellow,  white,  or  variegated  blos- 
soms and  are  valuable  additions  to  the  list  of  landscape  planting 
materials  available  for  the  hottest  interior  valleys. 


174  UNIVERSITY   OF  CALIFORNIA EXPERIMENT  STATION 


( CLIMATIC  .REQUIREMENTS 

Altitude. — Aaronsohn  reports  the  pomegranate  growing  and  thriv- 
ing in  Palestine  at  elevations  of  1000  to  1300  feet,  some  varieties  doing 
better  at  sea  level  or  near  the  coast  and  others  at  higher  elevations. 
On  the  interior  high  plateau  of  Spain,  pomegranate  growing  has 
reached  a  high  stage  of  perfection,  the  fruit  being  noted  for  its  superior 
quality.  The  bush  is  found  wild  on  the  hillsides  in  the  Russian  Cau- 
casus at  elevations  of  2000  to  3000  feet.  Pomegranates  flourish  on 
the  Deccan  plateau  of  India  at  elevations  of  3000  to  4000  feet.  In 
South  America  the  tree  is  reported  growing  in  Peru  at  high  elevations, 
while  in  Mexico  it  flourishes  on  the  interior  plateaus.  Fruit  of  very 
fine  quality  is  grown  in  Arizona,  New  Mexico,  and  Texas,  as  well  as 
in  the  Great  Basin  region  at  elevations  ranging  from  below  sea  level 
to  4000  feet.  In  California  the  experiment  station  reports  the  fruit 
as  doing  exceptionally  well  in  the  Sierra  foothills.  Here  the  pome- 
granate grows  and  fruits  at  elevations  where  considerable  snow  falls 
in  the  winter. 

Thus  we  may  conclude,  from  all  the  information  available  regard- 
ing elevation,  that  the  pomegranate  flourishes  and  fruits  in  perfection 
in  a  wide  range  of  altitudes  ranging  from  below  sea  level  to  4000  feet. 

Rainfall. — The  pomegranate  is  essentially  a  desert  plant,  being  well 
adapted  to  withstanding  long  periods  of  drought.  However,  under 
such  conditions,  little  fruit  is  borne.  Specimens  may  be  found,  still 
alive  and  holding  their  own,  on  old  abandoned  homesteads  in  the 
deserts  of  southern  California  and  Arizona,  which  on  application  of 
water  will  quickly  recover  and  fruit  again.  On  account  of  this  great 
resistance  to  drought,  it  would  seem  that  more  general  planting  of 
the  better  varieties  would  be  justified  in  those  regions  where  water 
is  scarce,  or  the  regular  supply  subject  to  interruptions. 

On  the  other  hand,  the  pomegranate  will  grow  and  fruit  under 
conditions  of  heavy  rainfall.  This  is  the  case  in  Florida  and  in  the 
other  southern  states,  as  wTell  as  in  Hawaii,  India,  and  the  Philippines. 
However,  fruit  produced  in  these  regions  is  of  poor  keeping  and  ship- 
ping qualities,  being  soft  and  succulent,  as  well  as  only  fair  in  eating 
quality. 

The  most  satisfactory  rainfall  conditions  for  the  production  of 
pomegranates  are  those  found  in  the  Sacramento,  San  Joaquin,  Im- 
perial, and  Coachella  valleys  in  California,  and  in  the  irrigated  valleys 
of  southern  Arizona  and  Sonora,  Mexico.  In  California  the  year  is 
divided  into  two  seasons,  wet  and  dry,  the  dry  coinciding  with  the 


THE  POMEGRANATE  175 

growing  season  of  the  pomegranate.  The  rainy  season  is  late  and 
short,  beginning  in  November  and  usually  ending  about  the  first  of 
March.  From  March  until  November  the  weather  is  usually  clear 
and  sunny  and  from  May  to  October  very  hot  and  dry.  The  pome- 
granate requires  a  long  growing  season,  since  it  blooms  in  May,  but 
the  fruit  does  not  ripen  ordinarily  until  October  or  November.  In 
the  dry,  hot  climate  of  the  Imperial  and  Coachella  valleys  the  fruit  is 
edible  as  early  as  the  middle  of  June,  and  ripens  in  August  and  Sep- 
tember. For  best  results  this  season  should  be  dry,  for  under  these 
conditions  fruits  of  excellent  eating  quality  as  well  as  remarkable 
keeping  quality,  is  produced.  Such  conditions  are  found  in  the  south- 
western United  States  and  northwestern  Mexico,  as  well  as  in  Palestine 
and  Spain. 

Temperatures. — One  of  the  limiting  factors  in  pomegranate  grow- 
ing is  temperature.  Although  more  hardy  than  citrus,  the  tree  is  not 
in  the  same  class  as  the  stone  fruits  and  cannot  endure  temperatures 
lower  than  8  to  15  degrees  F.  without  serious  damage,  and  is  frozen 
to  the  ground  by  zero  temperatures.  As  it  blooms  late  in  the  spring 
there  is  little  danger  from  frost.  Reasoner  states  that  the  freeze  of 
1886  in  the  South  killed  all  the  sweet  pomegranates  to  the  ground, 
but  did  little  damage  to  sour  varieties.  This  greater  frost  resistance 
of  the  sour  varieties  has  been  noted  several  times.  Zakuro  reports  the 
pomegranate  as  hardy  as  the  fig  in  Japan.  Blair  and  Hastings  state 
that  the  pomegranates  at  the  experimental  farm  near  San  Antonio, 
Texas,  are  occasionally  frost-injured. 

On  the  other  hand,  we  know  no  climate  that  is  too  hot  for  the 
pomegranate.  At  Aden,  Arabia,  where  the  summer  temperatures  are 
so  high  that  Europeans  are  said  to  rarely  venture  out  except  at  night, 
the  pomegranate  thrives  wherever  it  has  water.  It  may  be  classed, 
in  point  of  temperature  requirements,  with  the  fig  and  the  olive, 
although  because  of  its  different  blooming  period  it  regularly  fruits 
in  regions  of  somewhat  lower  average  temperature  than  either. 

For  the  proper  maturing  of  the  fruit,  the  sum  of  daily  mean  tem- 
peratures during  the  growing  period  must  be  high.  The  best  fruit, 
both  in  size,  color,  and  quality,  is  produced  in  those  districts  where 
the  summation  of  heat  units  received  is  very  high.  Pomegranates  from 
desert  regions  are  noted  for  their  fine  flavor  and  color.  In  the 
Old  World  they  are  often  interplanted  with  figs  and  other  semi-tropical 
fruits  between  the  date  palms.  On  the  other  hand,  fruit  of  fair  quality 
can  be  produced  in  regions  where  dates  cannot  be  grown  commercially, 
due  to  the  humidity  of  the  atmosphere. 


176  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

Pomegranates  seldom  ripen  well  in  California  near  the  Pacific  coast 
or  in  cool  regions,  usually  remaining  very  sour  and  tart,  as  well  as 
poorly  colored.  Moreover,  the  ratio  of  acid  to  total  solids  runs  high, 
and  when  exposed  to  cool  sea  breezes,  the  plant  does  not  bloom  well 
or  set  much  fruit. 

We  may  conclude  then,  that  using  the  proper  varieties,  pome- 
granate culture  is  limited  to  those  districts  with  altitudes  up  to  4000 
feet,  with  long,  hot,  dry  summers,  and  situated  in  a  belt  about  the 
earth,  extending  in  width  from  the  forty-first  parallel  south  latitude 
to  the  forty-first  parallel  north  latitude. 

PEOPAGATION 

The  pomegranate  is  very  easy  of  propagation,  which  may  be  accom- 
plished by  seedage,  cuttage,  and  layerage. 

Hardwood  Cuttings. — The  only  method  of  propagation  used  com- 
mercially is  by  hardwood  cuttings.  These  will  grow  in  the  open  ground 
about  as  readily  as  willow  cuttings.  The  stand  obtained  is  very 
satisfactory  and  the  method  used  very  simple.  In  February  or  March 
hardwood  cuttings,  ten  to  twelve  inches  long  and  one-quarter  to  a 
half  inch  in  diameter  are  cut,  usually  from  the  shoots  or  suckers,  and 
are  planted  in  the  open  ground  in  nursery  rows.  These  rows  are 
ordinarily  three  feet  apart  and  the  cuttings  spaced  eight  to  ten  inches 
in  the  row.  The  cuttings  should  be  thrust  almost  their  entire  length 
into  the  earth,  leaving  only  the'  top  eye  exposed.  This  eye  is  forced 
out  and  grows  into  the  tree.  Cuttings  of  this  sort  grow  thriftily  and 
are  often  ready  for  transplanting  to  the  orchard  or  hedge  by  the 
following  spring,  although  they  are  frequently  left  in  the  nursery 
row  two  seasons.  Hardwood  cuttings  are  sometimes  cut  in  the  fall 
and  callused  in  sand  over  winter,  then  set  out  in  early  spring.  This 
may  result  in  a  little  earlier  growth  and  consequently  a  larger  tree 
that  season,  but  is  not  necessary  to  insure  striking  root. 

Softwood  Cuttings. — Propagation  is  sometimes  accomplished  later 
in  the  season  by  the  use  of  softwood  cuttings.  These  will  grow  if 
given  careful  attention.  Best  results  are  obtained  by  rooting  them  in 
cutting-beds  or  green-houses.  They  strike  roots  in  several  weeks  and 
if  properly  cared  for,  may  be  set  out  the  following  spring.  As  this 
practice  possesses  no  special  advantages  it  is  little  used. 

Layerage. — The  pomegranate  layers  about  as  readily  as  the  grape. 
This  method  is  little  used,  however,  as  propagation  by  cuttings  is  so 
easy. 


THE  POMEGRANATE 


177 


Seedage. — Pomegranate  seeds  germinate  readily  without  under- 
going any  resting  period.  As  the  fruit  keeps  in  storage. until  Febru- 
ary or  March  without  any  difficulty,  seeds  may  be  taken  directly  from 
the  fruit  and  planted.  These  are  usually  placed  in  flats  and  kept  in 
a  cold-frame  or  hot-house  until  the  seedlings  are  well  established.     A 


Fig.  8. — Color  variation  in  fruits  from  the  progeny  of  one  Wonderful  pomegranate. 
Abscissa,  type  color  of  fruit.     Ordinate,  number  of  seedling  plants. 


fair  stand  is  usually  obtained.  This  method  of  propagation  should  not 
be  used  commercially  as  the  seeds  do  not  come  true  to  variety,  the 
range  of  variation  in  fruit  obtained  from  the  seed  of  a  single  pome- 
granate being  very  wide. 

A  study  of  seedling  pomegranates  made  by  J.  E.  Coit  in  1914-1915 
showed  that  the  normal  range  of  variation  to  be  expected  is  very  great. 


178 


UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 


In  1909  the  seeds  from  two  pomegranates  of  widely  differing  type  and 
variety  were  planted  in  separate  rows  at  the  experiment  station  at 
Meloland  in  the  Imperial  Valley.  One  fruit  was  from  Porto  Rico, 
pale  yellow  in  color,  with  a  scanty  supply  of  insipid  juice,  and  hard, 
bony  seeds  which  were  absolutely  inedible.     The  other  was  of  the 


§  8  SMlTOTo 


jvj 


j\! <3_ 


M      ^       iq     to      (o 


J£ St 


Fig.  9. — Size  variation  in  fruits  from  progeny  of  one  Wonderful  pomegranate. 
Abscissa,  average  weight  in  grams.     Ordinate,  number  of  seedling  plants. 


Wonderful  variety.  In  1914-1915  these  trees  were  in  full  bearing  and 
at  this  time  two  fair  sample  fruits  from  each  tree  were  selected  for 
study.  These  were  carefully  weighed,  measured,  and  described  separ- 
ately. In  both  varieties  a  wide  degree  of  variation  in  all  characters 
was  noted.  Every  degree  of  variation  in  fruit  and  flesh  color  in  a 
series  from  pale  yellow  to  deep  crimson  was  obtained ;  much  variation 


THE  POMKGRANATK  179 

in  the  length  of  calyx-tube  and  sepals  was  found ;  a  great  variation 
in  size  and  weight,  thickness  of  rind,  hardness  of  seed,  and  amounts 
of  pulp  and  flesh  were  observed.  The  results  obtained  in  this  study 
are  shown  in  figs.  8  and  9  and  emphasize  the  fact  that  propagation 
should  always  be  by  cuttings  from  plants  of  known  desirable  type. 


SOILS 

While  the  pomegranate  is  not  at  all  exacting  in  its  soil  require- 
ments, the  weight  of  evidence  tends  to  show  that  yields  are  heaviest 
and  quality  best  on  deep  soils  of  a  fairly  heavy  nature.  Pomegranates 
have  been  planted  in  California  on  many  soil  types,  ranging  from 
almost  pure  sand  to  heavy  clay,  and  have  grown  and  fruited  with  a 
greater  or  less  degree  of  success.  Experience  has  shown  that,  while 
the  tree  grows  on  light  soils,  yields  are  much  lighter  and  the  color 
much  poorer  than  on  the  heavier  types.  While  the  pomegranate  is 
quite  resistant  to  alkali  it  cannot  be  expected  to  produce  the  best 
quality  fruit  on  soils  strongly  impregnated  with  alkali.  The  same 
might  be  said  regarding  moisture  conditions.  The  soil  should  be  fairly 
well  drained,  although  the  tree  will  thrive  and  fruit  on  soils  rather 
heavier  and  wetter  than  those  used  for  pears.  In  fact,  the  pome- 
granate is  remarkable  for  the  amount  of  water  in  the  soil  it  will 
endure. 

ORCHAED  MANAGEMENT 

Planting  Systems. — At  the  present  time  pomegranates  are  most 
commonly  grown  in  hedge  form  or  as  border  trees,  although  some 
plantings,  especially  the  more  recent  ones,  have  been  made  in  orchard 
form.  When  planted  as  hedges  or  border  rows  the  bushes  may  be 
spaced  as  close  as  six  to  eight  feet,  growing  together  with  limbs  inter- 
locked so  that  a  compact  hedge  is  formed.  The  pomegranate  is 
especially  well  adapted  to  this  style  of  planting,  as  it  suckers  readily 
and  soon  forms  a  dense,  impenetrable  wall. 

Planting  distances  when  the  trees  are  set  in  orchard  form  have 
not  been  standardized  as  yet  and  vary  considerably.  The  consensus 
of  opinion  of  growers  in  various  parts  of  the  state  regarding  the  cor- 
rect distances  for  pomegranates  is  that  they  should  be  spaced  fourteen 
to  eighteen  feet  on  the  square  system. 

Inter 'planting. — Pomegranates  are  used  to  some  extent  as  inter- 
plants.  At  the  present  time  some  are  being  interplanted  with  olives 
at   eighteen   feet,   the   hexagonal   system   being  used.      Some   orange 


180 


UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 


groves  are  interset  with  pomegranates.  When  this  is  done  the  usual 
form  of  planting  is  the  triangle  system,  with  the  pomegranates  set 
twelve  by  twenty-four  feet  apart. 

PI  (tilling  Season. — Pomegranate  trees  should  be  planted  as  early 
in  the  spring  as  the  ground  can  be  readily  worked  and  is  not  too  wet. 
However,  as  the  pomegranate  starts  growth  comparatively  late  in  the 
spring,  late  planting  is  not  accompanied  by  such  disastrous  effects  as 
is  the  case  with  the  stone  fruits.  The  best  results  seem  to  be  obtained 
by  planting  in  February  and  March,  as  the  tree  then  has  a  chance 


Fig.   10. — Irrigating  flume  serving  pomegranates  on  the  right.     Orange  orchard 

on  the  left. 


to  get  well  established  in  place  and  to  grow  some  feeding  roots  before 
leafing  out. 

Preparation  of  the  Land. — Previous  to  planting,  the  land  should 
have  been  well  plowed  and  cultivated.  If  the  soil  is  in  good  condition, 
little  care  other  than  irrigation  and  two  or  three  cultivations  during 
the  season  is  needed  after  planting.  In  older  orchards  the  soil  should 
be  stirred  at  least  once  a  month  during  the  growing  season.  The  object 
is  to  maintain  a  good  soil  mulch  to  conserve  the  soil  moisture.  Culti- 
vation practice  varies  greatly  among  growers,  and  while  some  report 
good  crops  obtained  with  little  or  no  cultivation,  the  best  results  seem 
to  be  obtained  by  a  judicious  use  of  the  cultivator  and  spring-tooth 
harrow. 


THE  POMEGRANATE  181 

Irrigation. — Although  the  pomegranate  will  endure  extended  periods 
of  drought,  it  requires  about  as  much  water  as  peaches  or  apricots  to 
fruit  abundantly.  Commercial  practice  varies  considerably  in  the 
amount  of  water  applied.  Some  growers  irrigate  but  little,  while 
others  apply  as  much  as  they  give  their  citrus  orchards.  The  informa- 
tion available,  however,  seems  to  indicate  that  for  best  results  a 
moderate  amount  of  water  should  be  given  the  trees.  If  we  set  the 
water  requirements  of  orange  trees  at  fifty  inches,  including  the 
rainfall,  we  may  consider  that  the  pomegranate  requires  thirty-five  to 
forty  inches.  Some  of  this  water  comes  as  rain  in  the  winter  season. 
The  rest  is  usually  applied  in  two  to  five  irrigations,  distributed 
through  the  growing  season.  Some  growers  irrigate  until  July  only. 
Others  apply  water  once  a  month  until  September.  The  furrow  system 
is  used  almost  universally.    A 

Priming. — Pruning  of  the  pomegranate  is  a  subject  on  which  there 
exists  a  wide  diversity  of  opinion  among  growers  and  a  corresponding 
diversity  in  pruning  practice.  Some  prune  severely,  others  mod- 
erately, but  the  usual  practice  is  to  do  nothing  except  to  cut  out 
interfering  branches  and  dead  wood. 

Depending  on  the  form  desired  and  the  method  of  planting,  the 
pomegranate  needs  different  treatment.  Pomegranates  are  grown  in 
hedge  form,  border  rows,  and  orchard  form  and  each  requires  a  differ- 
ent sort  of  training.  When  grown  as  a  hedge  it  is  customary  to  let 
the  plants  grow  as  they  will  without  any  pruning  whatever.  "When 
grown  in  orchards  some  prefer  the  bush  form,  some  the  tree  form 
with  a  single  trunk.  On  account  of  the  large  amount  of  suckering  to 
be  done  the  first  few  years,  it  is  difficult  to  train  the  pomegranate  into 
the  tree  form,  but  it  can  be  done  especially  if  the  trunk  is  kept  firmly 
tied  to  a  strong  stake  during  the  first  few  years.  If  headed  too  high, 
plants  of  the  tree  form  are  likely  to  be  blown  over  by  strong  winds. 
Correspondence  with  many  of  the  pomegranate  growers  in  the  state 
indicated  that  they  were  more  inclined  to  the  bush  than  the  tree  form. 

To  prune  intelligently,  one  must  consider  the  fruiting  habit,  and 
habit  of  growth  of  the  tree.  The  pomegranate  is  a  vigorous  grower, 
sending  up  each  year  a  number  of  shoots  from  the  root  which  gives 
the  plant  a  bush  form  unless  otherwise  trained.  The  fruit  is  borne 
terminally  on  short  spurs  produced  on  slow-growing  mature  wood. 
This  wood  bears  for  several  years  but  as  the  tree  increases  in  size  this 
wood  loses  its  fruiting  habit,  which  is  assumed  by  the  younger  growth. 
Little  or  no  fruit  is  produced  in  the  interior  of  the  tree.  Thus  we 
have  the  fruit  produced  in  an  outer  zone  or  shell  which  gradually 
grows  farther  away  from  the  body  of  the  tree. 


182  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

Bearing  this  in  mind,  it  can  be  clearly  seen  that  a  heavy  pruning, 
especially  shortening  in  of  the  older  wood,  will  greatly  reduce  the 
crop  for  the  next  two  or  three  years.  A  correlation  between  small 
crop  and  heavy  pruning  has  been  noted  in  several  commercial  orchards. 
In  every  instance  where  the  grower  has  pruned  heavily,  the  crop  is 
comparatively  light  and  where  growers  have  practiced  moderate  prun- 
ing or  none  at  all,  the  tree  is  reported  as  a  heavy  bearer. 

It  should  be  borne  in  mind  that  the  market  demands  a  large 
pomegranate  and  will  pay  well  for  it.  'Jumbo'  fruits  bring  a 
premium,  while  small  fruit  sells  at  a  heavy  discount.  Therefore  the 
aim  should  be  size  and  quality,  rather  than  quantity.  A  large  pome- 
granate weighs  two  or  three  pounds,  and  it  is  not  unusual  for  an  old 
tree  to  bear  400  to  500  pounds  of  fruit.  To  stand  up  under  such  a 
load  the  tree  must  have  a  strong  framework. 

From  all  the  information  available  at  the  present  time  we  may 
outline  a  system  of  pruning  for  the  tree  form  about  as  follows :  When 
the  tree  is  planted  it  should  be  cut  back  to  a  whip  at  about  twenty-four 
to  thirty  inches  from  the  ground.  As  the  buds  put  out  and  shoots  are 
produced,  these  should  be  selected  and  thinned  out  to  three  or  five 
or  more  scaffold  branches  which  should  be  pinched  back  to  make  them 
stocky.  These  should  be  spaced  some  distance  apart,  the  lowest  at 
least  eight  or  ten  inches  from  the  ground,  and  symmetrically  arranged 
on  the  stem.  The  following  winter  the  scaffold  branches  should  be 
shortened  in  about  three-fifths  of  their  length.  In  the  spring  the  new 
shoots  arising  from  the  scaffold  branches,  primary  branches,  should 
be  restricted  to  two  or  three  per  limb.  The  main  stem  and  frame 
limbs  should  be  kept  free  from  suckers  at  all  times.  The  aim  in 
pruning  while  the  tree  is  young  is  to  train  the  plant  to  the  tree  form 
and  to  induce  the  formation  of  a  stocky,  compact  framework.  This 
should  be  accomplished  by  the  end  of  the  second  or  third  year. 

After  the  framework  has  been  established  all  the  growth  is  left  and 
the  tree  comes  into  bearing.  From  this  time  to  the  age  of  fifteen  or 
twenty  years,  the  tree  increases  slowly  in  size  and  yield.  Pruning 
after  the  third  year  should  be  confined  to  a  regular  removal  of  all 
sucker  growth  arising  from  the  root,  and  interfering  branches  as  well 
as  dead  brush,  and  an  annual  thinning  out  or  removal  of  some  of  the 
older  branches.  This  should  be  done  after  the  leaves  fall  in  winter. 
If  this  system  is  followed,  a  strong,  upright  tree,  bearing  200  to  400 
pounds  of  large,  well  formed  and  colored  fruit  can  be  obtained,  pro- 
vided other  conditions  are  favorable.  In  training  to  the  bush  form 
the  same  general  procedure  is  followed  except  that  at  the  beginning 
from  three  to  five  main  stems  are  selected  instead  of  one.     * 


THE  POMEGRANATE 


183 


Harvesting,  Packing,  and  Marketing. — On  account  of  the  common 
habit  of  splitting  the  fruit  of  most  varieties  of  pomegranates  must  be 
picked  before  fully  mature.  In  some  varieties  the  fruit  bursts  wide 
open  on  maturity  and  the  arils  dehisce  after  the  fashion  of  peas  from 
a  pod.  In  others  it  cracks  just  enough  to  expose  the  arils  and  spoil 
the  fruit.  There  is  much  variation  regarding  this  tendency.  Some 
trees  will  hold  their  fruit  until  winter  and  never  show  any  splits. 


Fig.  11. — California  pomegranates;    standard  commercial  pack. 


Others  may  have  a  high  proportion  of  bad  splits.     To   avoid   this 
difficulty  most  of  the  fruit  is  picked  before  fully  ripe. 

Fortunately  the  pomegranate  is  one  of  those  fruits  which,  after 
reaching  a  certain  degree  of  maturity,  continues  to  ripen  in  cold 
storage,  where  it  will  keep  in  excellent  condition  for  five  or  six 
months.  Not  only  does  it  ripen,  but  the  quality  is  improved,  the  flavor 
becoming  richer  and  more  vinous.  The  rind  shrinks  and  becomes 
thinner  and  tougher;  the  amount  of  rag  decreases;  the  seed  coats 
appear  to  become  more  tender  and  edible.  Several  pickings  should  be 
made,  the  first  about  the  first  week  in  October  and  two  or  three  others 
at  weekly  intervals. 


184  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

Pomegranates  are  very  securely  attached  to  the  fruiting  wood  by 
thick,  strong  stems,  and  should  be  clipped  rather  than  pulled.  If 
pulled  from  the  tree,  damage  may  be  done  in  breaking  the  limbs,  but 
it  is  almost  certain  that  the  stem  will  pull  loose  from  the  fruit,  taking 
with  it  a  part  of  the  rind  about  the  base.  Care  should  be  taken  in 
handling  the  fruit  to  avoid  bruising,  as  it  is  quite  susceptible  to 
injury. 

The  fruit  is  gathered  in  picking  bags  and  emptied  into  field  boxes. 
These  are  hauled  to  the  packing-house,  usually  belonging  to  the  local 
citrus  association,  where  the  fruit  is  packed.  Here  it  is  brushed  or 
wiped  if  it  is  particularly  dirty,  although  this  process  is  usually 
omitted.  The  fruit  will  take  a  high  polish,  making  it  very  attractive, 
and  wiping  would  seem  well  worth  while.  It  is  next  sized,  the  sizes 
running  from  24  to  110  per  box.  After  sizing,  the  fruit  is  wrapped 
in  tissue  paper  and  packed. 

The  commercial  package  used  is  the  orange  half-box,  made  of  six 
pieces,  two  each  for  the  top  and  bottom,  and  one  for  each  side.  When 
packed,  these  boxes  average  thirty-five  to  forty  pounds  in  weight. 
Care  taken  in  packing  the  fruit  is  well  repaid,  for  pomegranates  are 
sold  partly  for  their  ornamental  value,  the  price  varying  widely 
according  to  the  size  of  the  fruit  and  the  neatness  of  the  pack. 

The  demand  for  pomegranates  is  very  unstable  as  yet,  and  markets 
are  easily  glutted.  This  is  largely  due  to  a  lack  of  knowledge  on  the 
part  of  the  great  body  of  consumers  as  to  the  merits  of  the  fruit, 
as  well  as  to  the  fact  that  the  pomegranate,  still  being  used  largely  for 
decorative  purposes,  is  regarded  as  a  luxury.  There  is  some  demand 
for  the  fruit  to  be  used  for  decorative  purposes  in  presentation  baskets 
of  assorted  fruits,  in  retail  displays,  on  banquet  tables,  and  in  prepar- 
ing various  kinds  of  punch.  This  kind  of  demand  is  almost  entirely 
from  American  consumers  in  eastern  markets,  where  nearly  all  the 
commercial  pomegranate  crop  is  disposed  of.  Such  markets  as  Chicago, 
New  York,  and  Philadelphia  take  small  shipments  of  good  fruit  regu- 
larly at  very  satisfactory  prices. 

A  few  people  in  the  east,  particularly  Greeks  and  Slavonians,  buy 
the  fruit  for  eating  out  of  hand.  The  markets  in  Los  Angeles  and 
San  Francisco  are  quite  limited  and  easily  oversupplied.  Here  the 
fruit  is  but  little  used  for  decorative  purposes,  being  consumed  chiefly 
by  Indians,  Mexicans,  and  people  from  the  Mediterranean  countries, 
who  eat  the  fruit  out  of  hand. 

Pomegranates  are  often  dispatched  by  the  carload  lot,  but  a  com- 
mon practice  is  to  include  a  few  boxes  in  a  carload  of  oranges  or 


THE  POMEGRANATE 


185 


Emperor  grapes.     This   practice   avoids   overloading   a   market   and 
fruit  shipped  in  this  way  rarely  fails  to  bring  fair  prices. 

If  picked  with  long  stems  and  hung  up  to  cure  in  a  dry  room, 
pomegranates  will  keep  in  very  good  condition  for  several  months. 
The  rind  dries  and  hardens,  but  the  interior  remains  good  and  even 
improves.  The  farmers  in  Algeria  cure  large  quantities  of  pome- 
granates in  this  manner  every  year.  Since  the  fruit  keeps  so  well 
there  seems  to  be  no  reason  why  the  market  should  not  be  supplied 
with  them  for  from  six  to  eight  months  of  the  year. 


Fig.   12. — The  Wonderful  pomegranate  after  five  months  in  cold  storage. 


YIELDS  AND  RETURNS 

As  has  been  brought  out  in  previous  statements,  a  great  variation 
in  yields  has  been  reported  by  different  growers.  Orchards  situated 
on  sandy  soils  are  found  to  bear  light  crops.  Heavily  pruned  trees 
are  noticed  to  bear  small  crops.  We  may  then  conclude  that  yield  is 
influenced,  primarily,  by  the  nature  of  the  soil  and,  secondarily,  by 
the  method  of  pruning  practiced.  The  various  combinations  of 
these  two  give  rise  to  a  wide  range  of  variation  in  yields.  Individual 
trees  are  known  which  bear  regularly  ten  to  fifteen  packed  boxes. 

Prices  received  on  California  markets  do  not  run  as  high  as  those 
obtained  in  Eastern  cities.  The  price  on  the  San  Francisco  market 
fluctuates  from  65  cents  to  $1.50  per  box  during  the  season,  averaging 
75  to  80  cents.  Pomegranates  retail  at  relatively  high  prices  in  Cali- 
fornia. In  the  San  Francisco  Bay  region  in  early  season  the  fruit 
retails  at  three  for  25  cents,  later  at  5  cents  apiece,  and  rarely  goes 
lower  than  three  for  10  cents. 


186  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

A  study  of  the  prices  realized  for  California  pomegranates  sold 
at  auction  in  the  Chicago  market,  Monday,  October  25,  1915,  is  in- 
teresting. On  that  day  there  were  unloaded  and  sold  320  boxes  of 
pomegranates  in  seven  lots.  The  highest  price  received  was  $2.50  per 
half-box.  The  fruit  bringing  this  price  was  packed  in  two  layers, 
thirty-two  fruits  per  box.  This  is  one  of  the  largest  sizes  packed. 
The  lowest  price  received  for  an  undamaged  box  was  $1.35.  This 
fruit  was  packed  in  three  layers,  ninety  fruits  per  box.  Other  fruit 
packed  seventy-six  fruits  per  box  and  one  hundred  and  six  fruits 
per  box  brought  $1.40.  The  total  receipts  for  these  320  boxes  were 
$480.60,  making  the  average  price  $1.50  per  36-pound  box. 

According  to  the  census  figures  for  1910,  the  average  net  price 
returned  to  the  pomegranate  grower  in  the  United  States  is  3  cents 
per  pound,  which  would  be  about  $1.00  per  box. 

A  good  pomegranate  tree  should  yield  250  pounds  of  marketable 
fruit.  This  amount  will  pack  seven  half-boxes.  Using  the  average 
net  returns  for  last  season,  this  tree  would  return  the  grower  $5.95 
per  season.  The  cultural  costs  are  low,  but  assuming  these  to  be  $75.00 
per  acre  and  that  there  were  100  trees  to  the  acre,  the  returns  from 
a  first-class  orchard  would  amount  to  approximately  $500.00  per  acre. 
This  figure  seems  high  and  does  not  represent  the  average,  but  some 
growers  have  reported  such  returns  and  claim  that  their  pomegranates 
are  more  profitable  than  their  oranges.  It  should  be  borne  in  mind, 
however,  that  the  total  market  demand  is  yet  small  and  does  not 
justify  a  rapid  or  sudden  extension  of  pomegranate  planting.  As  the 
demand  is  growing  we  may  confidently  expect  a  gradual  and  perma- 
nent increase,  especially  if  the  growers  limit  shipments  to  first-class 
fruit  which  will  advertise  itself  and  thus  increase  the  demand. 

USES 

At  the  present  time  the  pomegranate  is  used  chiefly  in  eastern 
markets  for  decorating  fruit  stands  and  banquet  tables.  Fruit  retailers 
also  find  that  the  pomegranate  is  useful  in  increasing  their  variety  of 
fruits  and  in  attracting  the  attention  of  buyers.  It  is  also  useful  in 
the  preparation  of  mixed  gift  baskets  of  assorted  fruits.  The  red  arils 
and  crimson  juice  are  used  to  some  extent  in  salads,  punches,  and  fancy 
dishes.  In  the  southwest,  however,  by  far  the  greater  proportion  of 
the  fruit  is  eaten  fresh  out  of  hand. 

The  sweet  pomegranate,  the  only  sort  grown  for  market,  when 
perfect,  possesses  a  fresh  crispness,  delicacy,  and  sprightliness  of  flavor 
almost  unrivaled  among  fruits.     It  is  deemed  a  great  luxury  by  those 


THE  POMEGRANATE 


187 


who  are  accustomed  to  it  in  its  perfection.  There  is  a  knack  in  open- 
ing the  fruit  and  shelling  out  the  arils,  which  the  novice  only  acquires 
with  practice,  but  at  which  the  Mexicans  and  southern  Europeans  are 
very  dextrous  (see  Fig.  13). 


Fig.    13. — The   knack   of   opening  a   pomegranate.     A   circular   disc   is   cut   from 

the  calyx  end,  the  rind  divided  into  segments  by  following  the  partition  walls,  the 

segments  forced  apart  and  the  arils  shelled  out. 


In  Syria  the  fruit  is  cut  open,  the  arils  are  extracted  and  stewed 
with  sugar,  sprinkled  with  rose  water,  and  served  on  little  plates,  this 
being  considered  a  dish  of  rare  excellence. 

From  ancient  times  the  Mediterranean  peoples  have  used  the  pulp 
in  making  acescent  and  cooling  drinks.  The  juice  is  particularly 
satisfying  during  fevers  or  in  hot  weather,  assuaging  thirst  to  a 
marked  degree.  An  infusion  of  the  crushed  seeds  in  cool  sweetened 
water  is  greatly  appreciated  by  convalescents.     The  pomegranate  is 


188  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION 

considered  superior  to  the  lemon  for  summer  drinks  by  many  people. 
The  inhabitants  of  southern  Russia  and  Armenia  make  a  commercial 
drink  called  Nasharab  from  the  juice  which  is  said  to  be  very  good. 

A  very  delicate  wine  was  prepared  from  pomegranate  juice  by  the 
ancient  Jews.  Grath  Rimmon,  the  name  of  a  certain  village,  signifies 
Press  of  the  Pomegranate.  In  France  the  juice  is  mixed  in  certain 
proportions  with  grape  juice  and  a  wine  made  which  is  highly  esteemed. 
The  Balkan  peoples  manufacture  a  wine  from  the  pomegranate,  which 
constitutes  an  important  industry  in  those  countries.  Professor  W.  V. 
Cruess  of  the  University  of  California  has  made  a  good  grade  of  wine 
and  a  fair  claret  from  pomegranate  juice. 

The  pomegranate  is  coming  more  and  more  to  be  regarded  as  a 
fruit  of  great  possibilities  for  use  in  the  soft  drink  trade.  For  this 
use  its  chief  value  lies  in  its  high  juice  content.  The  flavor  is  strik- 
ingly sweet  and  aromatic,  and  the  color  of  red  varieties  is  beautiful 
crimson.  The  acid  content,  chiefly  citric,  is  small,  about  0.6  to  1.0 
per  cent,  or  similar  to  that  of  sweet  strawberries.  The  sugar  content 
of  the  juice  varies  from  about  12  to  17  per  cent.  There  is  an  aromatic 
principle,  not  volatile  or  capable  of  distillation,  which  seems  to  be 
contained  in  the  extractive  matters.  In  good  pomegranates  the  juice 
yield  is  about  75  per  cent  of  the  weight  of  the  fruit,  or  sixty  to  seventy- 
five  gallons  per  ton.  The  seeds  average  7  to  8  per  cent  of  the  weight 
of  the  fruit. 

Analyses  of  the  fruit  by  the  California  Station  in  1903  and  by  the 
Hawaiian  Agricultural  Experiment  Station  in  1913  show :  Edible  por- 
tion, 56  per  cent;  water,  76.8;  protein,  1.5;  fat,  3;  sugar  14  to  16; 
crude  fiber,  3  to  4 ;  ash,  .6.  It  is  interesting  to  note  that  pomegranates 
contain  more  sugar  than  apricots,  plums,  peaches,  or  oranges. 

Considerable  difficulty  is  encountered  in  expressing  the  juice,  as 
the  rind  is  bitter,  containing  tannin,  and  ordinary  crushing  methods 
cannot  be  used.  At  present,  the  fruit  must  be  cut  open  and  the  arils 
removed  for  pressing.  If  varieties  of  pomegranates  can  be  procured 
by  breeding  or  introduction  which  have  little  pulp  and  thin  rinds 
and  are  relatively  low  in  tannin  content,  it  is  entirely  possible  that  a 
process  of  extracting  the  tannin  may  be  worked  out  so  that  the  neces- 
sity of  laboriously  removing  the  arils  before  crushing  may  be  obviated. 
The  juice,  when  cooked  with  an  equal  amount  of  sugar,  produces  a 
beautiful  red-colored  syrup  which  is  greatly  improved  by  the  addition 
of  a  little  lemon  syrup.  This  serves  to  bring  out  the  aromatic  flavor 
and  increase  the  acidity.  A  syrup  of  this  nature  constituted  the  orig- 
inal grenadine  syrup,  much  used  in  Europe  in  the  preparation  of  soft 


THE  POMEGRANATE  189 

drinks.  Very  refreshing  carbonated  drinks,  equal  to  any  of  our 
common  carbonated  beverages,  can  be  made  by  using  this  syrup  as  the 
base.  Confectioners  sometimes  use  the  red  juice  of  the  Wonderful 
variety  for  coloring  candies,  ice  cream,  and  other  things. 

Pomegranate  juice,  when  sterilized  in  its  natural  form  and  pre- 
served in  bottles,  is  excellent,  and  in  the  opinion  of  many,  equal  to 
the  best  grape  juice.  It  does  not  possess  that  cloying  sweetness  which 
so  many  people  object  to  in  grape  juice  made  from  European  varieties. 

Jellies  and  preserves  can  be  made  from  the  pomegranate  if  a  little 
orange  or  lemon  peel  is  added  to  furnish  the  pectin. 


Fig.  14. — The  arils  from  a  single  fruit  make  a  highly  attractive  dish.     (Keduced.) 

A  dye  is  extracted  from  the  bark  which  is  used  in  staining  morocco 
leather.  The  flowers  furnish  a  pale  yellowish-red  dye  while  the  rind 
of  the  fruit  yields  a  jet-black  indelible  ink. 


ft 


DISEASES  AND  INSECT  PESTS 


The  pomegranate  has  been  singularly  free  from  diseases  of  any 
economic  importance.  Indeed,  most  growers  claim  that  their  trees  are 
absolutely  free  from  disease.  However,  there  has  recently  appeared 
a  new  disease  which  may  prove  a  limiting  factor  in  pomegranate 
culture. 

Heart  Rot. — When  an  infected  fruit  is  opened,  the  central  cavity 
is  found  filled  with  a  disgusting  mass  of  decayed  arils,  black  in  color 


190  UNIVERSITY  OF   CALIFORNIA EXPERIMENT  STATION 

and  disagreeable  in  odor.  The  deeay  usually  shows  no  connection 
with  the  rind,  being  entirely  surrounded  by  sound  flesh.  It  is  some- 
times quite  difficult  to  detect  infected  fruit  from  exterior  appearances, 
although  experienced  pickers  are  able  to  discard  most  of  the  infected 
fruits  as  it  is  imperative  that  they  be  excluded  from  commercial 
packs.  Infection  takes  place  in  the  blossom  and  the  progress  of  the 
fungus  may  be  traced  by  a  thread-like  black  line  of  decay  from  the 
stigma  down  through  the  stylar  canal  into  the  interior  of  the  fruit. 

Coit  found  this  rot  interfering  with  the  shipping  of  pomegranates 
at  Mesa,  Arizona,  as  early  as  1907.  In  1910  Kearney  reported  it  from 
Indio,  California,  Sacaton  and  Phoenix,  Arizona,  and  San  Antonio, 
Texas.  Recently  specimens  have  been  received  at  Berkeley  from  vari- 
ous parts  of  the  San  Joaquin  Valley.  Here  at  Berkeley  various 
persons  in  the  Divisions  of  Plant  Pathology  and  Citriculture  have 
made  cultures  repeatedly  over  a  period  of  several  years  with  the  uni- 
form result  of  finding  an  alternaria  present  in  pure  culture  in  the 
interior  of  the  fruits.  And  yet  this  rot  is  apparently  the  same  as  that 
studied  by  McMurran*  of  the  United  States  Department  of  Agricul- 
ture and  reported  as  due  to  Sterigmatocystis  castanea  Patterson. 

At  present  no  remedy  can  be  suggested  except  the  sanitary  pre- 
caution of  gathering  and  burning  all  rotten  fruits  found  about  the 
orchards. 

There  is  no  insect  which  seriously  infests  the  pomegranate  in 
California.  A  few  isolated  instances  where  a  single  tree  has  been 
attacked  by  some  insect  have  been  reported.  In  no  case,  however,  has 
the  damage  been  severe  enough  to  warrant  any  control  measures. 

Aspidiotus  camelliae  {Greedy  Scale.) — The  pomegranate  has  been 
reported  attacked  by  the  greedy  scale  in  Los  Angeles  County.  How- 
ever, the  damage  done  has  been  very  slight  and  but  few  infested  trees 
have  been  reported. 

Coccus  citricola  (Citricola  Scale). — Near  Porterville  an  orange 
orchard  infested  with  this  scale  joined  a  pomegranate  orchard.  The 
row  of  pomegranates  next  the  oranges  was  rather  heavily  infested  with 
scale,  but  there  appeared  to  be  little  tendency  for  the  scale  to  spread 
from  the  row  next  the  oranges  where  they  had  probably  been  blown 
by  the  wind. 

Scirtothrips  Citri  (Citrus  Thrips). — A  peculiar  rolling  of  the 
edges  of  the  leaves  frequently  noticed,  but  not  understood,  has  re- 
cently been  found  to  be  due  to  thrips.  Sometimes  the  fruit  also  is 
scarred,  but  ordinarily  the  damage  amounts  to  little.     In  midsummer 

*  Phytopathology,  vol.  2,  no.  3,  p.  125. 


THE  POMKGRANATI-: 


191 


the  thrips  concentrate  on  the  tender  growth  of  the  new  suckers  from 
the  roots,  causing  serious  damage  to  the  leaves  or  complete  defoliation 
of  certain  portions  of  the  shoots.  As  the  suckers  are  all  removed  (lur- 
ing the  next  pruning  season  the  harm  done  is  negligible.  It  lias  not 
been  found  necessary  as  yet  to  employ  any  control  measures. 

Virachola  Deudorix  livia  {Pomegranate  Butterfly) . — This  insect 
has  been  reported  by  Woodrow  in  India  and  by  Gough  in  Egypt.  The 
larva  or  caterpillar  does  the  damage,  infesting  the  interior  of  the 
fruit.  The  proportion  of  the  crop  attacked  is  quite  large  and  the 
damage  is  very  serious. 


Fig.   15. — Pomegranate  leaves  distorted  by  citrus  thrips  contrasted  with  normal 

leaves. 

Leptoglossus  Zonatus. — This  insect,  a  large  sucking  bug,  is  re- 
ported in  the  Salt  River  Valley  of  Arizona  as  causing  considerable 
damage  to  pomegranates  as  well  as  oranges  and  other  fruits.  The  bug 
is  about  three-fourths  of  an  inch  long  and  gray  in  color.  The  mouth 
parts  include  a  long  tube,  which  is  used  for  sucking.  The  insect 
excretes  a  dark  liquid  which  has  the  very  disagreeable  odor  so  char- 
acteristic of  the  stink-bug  family. 

"While  very  little  accurate  information  is  available  as  to  the  dam- 
age caused  by  this  bug,  it  is  known  to  breed  in  great  numbers  on  the 
pomegranate  bushes  and  to  suck  the  juice  from  the  exposed  arils  of 
split  pomegranates. 

In  Hawaii  the  Mediterranean  fruit  fly,  Ceratitis  capitata,  is  known 
to  attack  pomegranates. 


192  UNIVERSITY  OF   CALIFORNIA EXPERIMENT  STATION 


OTHER  TROUBLES 

Splitting. — At  the  ripening  period  the  pomegranate  is  very  sub- 
ject to  splitting.  This  is  a  natural  characteristic  of  the  fruit  but  is 
much  more  pronounced  in  some  cases  than  in  others.  It  varies  with 
locality,  variety,  and  even  in  individual  trees.  There  are  two  char- 
acteristic kinds  of  splits,  stem-end  splits  and  side  splits. 

Many  explanations  have  been  advanced  to  account  for  the  split- 
ting. It  has  been  attributed  to  early  frosts,  early  rains,  irregular 
irrigation,  light  irrigation,  and  many  other  things.  The  common  idea 
is  that  splitting  is  due  to  sudden  fluctuations  in  the  moisture  content 
of  the  soil  and  air,  caused  by  a  lack  of  irrigation  at  the  proper  times, 
or  hot,  dry  north  winds  followed  by  heavy  irrigation.  Splitting  is 
always  worse  in  the  case  of  fruit  which  is  allowed  to  become  over- 
mature on  the  trees. 

"While  quite  severe  in  some  sections,  very  little  definite  information 
is  available  as  to  the  causes  of  splitting.  There  are  varieties  or  strains 
which  are  not  seriously  affected.  The  trouble  may  be  largely  avoided 
by  picking  the  fruit  before  splitting  becomes  serious. 

Sun-scald  or  Sunburn. — Fruits  exposed  to  the  direct  rays  of  the 
sun  in  very  hot,  dry  regions  are  occasionally  sunburned.  This  is 
evidenced  by  a  dark  brown  color  and  a  very  tough,  leathery  condition 
of  the  rind  on  the  side  affected.  Sunburn  causes  the  fruits  to  be 
irregular  and  uneven  in  growth,  but  is  usually  not  of  any  great  im- 
portance. 

Internal  Breakdown. — The.  fruit  from  certain  districts  in  some 
seasons  is  affected  with  a  peculiar  condition  of  the  arils  resembling  that 
breakdown  or  deterioration  which  normally  occurs  during  senile  de- 
cline. This  condition  may  be  found  in  fruit  still  hanging  on  the 
tree  early  in  the  season,  when  it  should  normally  be  at  the  height  of 
its  life  activities.  The  arils  have  a  lighter  color  than  is  natural,  are 
rather  flat  in  taste  and  exhibit  a  streaked  appearance.  Many  delicate 
white  lines  radiating  in  all  directions  from  the  seed  to  the  outer  wall 
of  the  aril  can  be  seen.  It  appears  to  be  an  enzymatic  deterioration, 
as  no  organism  has  so  far  been  found  in  connection  with  it.  There  is 
apparently  no  way  of  determining  from  the  external  appearance  of 
the  fruit  whether  or  not  it  is  affected  with  this  trouble.  We  can  only 
compare  it  with  the  internal  browning  of  certain  kinds  of  apples  and 
say  that  both  are  probably  physiological  diseases,  the  nature  of  which 
are  not  as  yet  understood. 


